1. Field of the Invention
The present invention relates to obtaining 3D information, and more particularly, to an apparatus and method for matching a depth image and a 2D color image to obtain 3D information.
2. Description of the Related Art
In a conventional compact camera, which employs a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS), (hereinafter, referred to as a CCD/CMOS camera) when a photographing button in the CCD/CMOS camera is operated, the CCD/CMOS obtains a 2D color image of a subject by detecting visible rays reflected from the subject that receives sunlight or artificial light.
Also, when a photographing button in a depth camera is operated, the depth camera obtains a depth image of a subject, by irradiating infrared rays on the subject, calculating depth of each point of the subject considering points of time at which the infrared rays are irradiated and points of time at which the infrared rays reflected from the point are detected, and expressing the calculated depths in an image. Here, the depth denotes a distance between a point of the subject and the depth camera.
3D image information of the subject can be obtained by using a 2D color image of the subject and a depth image of the subject.
When a photographer photographs a subject twice using the CCD/CMOS camera and the depth camera, respectively, the subjects in the 2D color image and the depth image are generally different since specifications of the CCD/CMOS camera and the depth camera, such as a view angle and a focal distance, are different. Moreover, locations of the CCD/CMOS camera and the depth camera minutely differ whenever the subject is photographed due to hand shaking of the photographer, and thus the subjects in the 2D color image and the depth image are rarely identical. Even if the subjects in the 2D color image and the depth image are identical, the resolutions set in the CCD/CMOS camera and the depth camera are different. As a result, it is not easy to quickly and accurately determine which pixels forming the 2D color image match pixels forming the depth image.
Accordingly, a method of quickly and accurately matching the 2D color image and the depth image is required so that reliable 3D image information can be quickly obtained by using the separately obtained 2D color image and depth image.